The synthetic approach for preparing para-phenyl alkynyl benzaldehydes is well known. Several documents quote the use of para-phenyl alkynyl benzaldehydes as building block in the synthesis of various compounds, e.g. for the synthesis of electrically conductive polymers.
A Japanese application (JP 07138196, published on 30 May 1995), for instance, describes the following specific method. The method involves the use of a Palladium catalyst in two separate steps.

A further application related to para-phenyl alkynyl benzaldehyde, is PCT/EPO3/00808 (priority date: 29 Jan. 2002). It also implies the use of a palladium catalyst and discloses the following specific pathway for synthesizing para-phenyl alkynyl benzaldehyde:

The methods used in the art imply the use of costly Palladium catalysts. Furthermore, the use of Palladium catalysts causes Palladium contamination and frequently, formation of undesired by-products. The present invention provides a new method that does not require the use of Palladium catalysts.